Shift lever mechanism

ABSTRACT

A shift lever mechanism ( 10 ) comprises a housing ( 12 ), having a longitudinal axis ( 14 ), and a lever ( 16 ), having a first end ( 18 ), a second end ( 20 ) and a longitudinal axis ( 22 ). The mechanism ( 10 ) further comprises pivoting means ( 24 ) adapted to facilitate pivoting of the lever ( 16 ) into predetermined positions. The mechanism ( 10 ) further comprises lever position indication means ( 78 ) operable to indicate disposal of the lever in one or more positions, and resilient means ( 92 ), operable to provide resistance to displacement of the lever ( 16 ) into a predetermined restricted position. The pivoting means ( 24 ) is attached to the lever ( 16 ) and is disposed in a retaining cup ( 38 ), being operable to pivot therein. The retaining cup ( 38 ) is disposed in the housing ( 12 ). The lever position indication means ( 78 ) and the resilient means being disposed on the pivoting means ( 24 ).

FIELD OF INVENTION

The present invention relates to gear shift lever mechanisms,particularly to means operable to provide resistance to displacement,and means operable to indicate disposal, of the lever in one or morepredetermined positions.

BACKGROUND OF THE INVENTION

Normally, the shifting of ratios in a transmission system is effected bya shift finger acting on a set of transmission forks in thetransmission. The shift finger is acted on by a shift lever extendingoutside the transmission and supported in a supporting mechanism.

Conventionally, on a rear driven vehicle, the shift lever is directlyoperable on the transmission system and is mounted in a housingextending from the top thereof. On a forward driven vehicle, the shiftlever is normally remotely operable on the transmission system by meansof a remote control shift assembly. The remote control shift assemblynormally comprises a series of levers, or other means such as, forexample, cables or hydraulic mechanisms, to which the shift lever isconnected.

Known shift lever supporting mechanisms comprise an enlarged sphericalportion disposed on the shift lever. The spherical portion is arrangedin the mechanism in a retaining cup and is operable, throughsphere-to-sphere engagement, to pivot therein to perform shiftingoperations. The retaining cup is housed in a housing through which thelever extends.

Shift lever mechanisms also generally comprise biasing means operable toprovide a biasing force on the lever when it is shifted from apredetermined neutral position.

Known biasing means generally comprise a pair of diametrically opposingreturn pins operable to contact opposite side surfaces of the lever. Thereturn pins are disposed along an axis transverse to that of the leverin a biased neutral position and are operable to apply a biasing forceon the lower regions of the side surfaces of the lever. A gap, due tomanufacturing tolerances, normally exists between each side surface andthe associated return pin.

In use, pivotal displacement of the lever, from a neutral position,causes it to abut the relevant return pin and, on further displacementof the lever, displaces the return pin against the biasing force of aspring, thereby applying a returning force on the lever operable toencourage the lever back into the neutral position.

Means operable to provide resistance to displacement of the lever into apredetermined position is usually in the form of a biased detent pin,disposed in a transverse direction relative to the return pin, andadapted to provide resistance to displacement thereof. Because theresistance is provided relatively remote from the user, that is, at adistal end of the lever, and through biasing means, the user experiencesundesirable distant and non-responsive feel in the shifting action.Further, because of the relative remoteness of the detent from the usera relatively large spherical portion is required to provide sufficientleverage on the return pin to overcome the resistance provided by thedetent pin. Furthermore the resistance is only applicable on the leverin a direction in which a return pin is disposed.

Means operable to indicate disposal of the lever in one or morepredetermined positions are usually suitably disposed to be actuated bythe return pin or the detent pin. Again this is undesirable because ofthe above mentioned disadvantages.

The abovementioned known mechanisms experience undesirable movement ofthe lever due to biasing means, in the form of return pins, beingdisposed only in limited directional positions relative to displacementof the lever. In order to have a completely biased lever it would benecessary to have a return pin disposed in each direction in which thelever is displaceable. This would clearly be uneconomic as each returnpin requires a hole machined into the housing in which it is disposed.

Further, the gap between each side surface of the lever and theassociated return pin translates into undesirable movement of the lever,which is felt by a user.

Furthermore, the disposition of the return pins, transverse to thelongitudinal axis of the housing, and the length of travel required inthe pins to provide the desired biasing force, dictates the overallminimum width of the mechanism.

It is desirable for the user to experience a positive feel andpositional certainty when the lever is displaced into predeterminedpositions, including neutral positions.

Further, it is desirable to increase the functional efficiency of shiftlever mechanisms and to reduce costs related to manufacturing thereof.

Furthermore, a compact mechanism, the size of which is not dictated byelements thereof extending radially outwards from the longitudinal axisof the housing, is desirable.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a shift levermechanism operable to provide the user with positive feel and positionalcertainty of the lever.

It is also an object of the present invention to provide a shift levermechanism with increased functional efficiency.

Further, it is an object of the present invention to provide a shiftlever mechanism having relatively lower manufacturing costs.

Furthermore, it is an object of the present invention to provide a shiftlever mechanism which is compact, the size of which is not dictated byelements thereof extending radially outwards from the longitudinal axisof the housing.

According the present invention there is provided a shift levermechanism, comprising a lever, pivoting means, adapted to facilitatepivoting of said lever into a plurality of positions, and lever positionindication means, operable to indicate disposal of the lever in one ormore predetermined positions, wherein the pivoting means comprises aspherical element and the lever position indication means comprisestransducer means, disposed adjacent the spherical element to beco-operable with actuation means, such that, upon positioning of thelever in said each predetermined position, the actuation means actuatesthe transducer means to indicate, to a user, disposal of the lever insaid each predetermined position, characterized in that at least part ofthe actuation means is disposed on the spherical element.

The transducer means may comprise an electrical switch, which may be apotentiometer.

Alternatively, the transducer means may comprise an air valve.

The actuation means advantageously comprises a member and a receiveradapted to receive the member therein. The member may be disposed on thetransducer means and the receiver may be disposed on the pivoting means.

The transducer means may be disposed in the housing preferably along anaxis extending radially outwards and, more preferably, substantiallyperpendicular relative to the longitudinal axis of the housing.

Advantageously, at least part of the transducer means, preferably themember, is displaceable relative to at least part of the pivoting means,preferably the receiver. The displacement of the part is preferablyalong an axis extending radially outwards relative to the pivotingmeans.

A shift lever according to the present invention may also compriseresilient means, operable to provide resistance to disposal of the leverin one or more predetermined positions, characterized in that theresistance is provided by the pivoting means.

The resilient means may comprise a resilient member and a detent. Thedetent is preferably disposed on the pivoting means and the memberpreferably disposed on the housing substantially along an axis extendingradially outwards from the pivoting means. The member is preferablydisplaceable relative to the detent.

The pivoting means may comprise a spherical element advantageouslydisposed in a retaining cup and operable to pivotally move therein bysphere-to-sphere engagement therewith.

The spherical element may be fixed to the lever thereby forming a pivotpoint on the lever. The spherical element may be fixed to the lever bymeans of a retaining pins. Alternatively, the spherical element may forman integral part of the lever.

The lever may extend through the spherical element to form anarrangement substantially coaxial therewith.

The spherical element is preferably disposed on the lever intermediatefirst and second ends thereof.

The spherical element is preferably formed from a plastics material.Alternatively, the spherical element may be formed from a metallicmaterial.

The retaining cup may be formed from a plastics material. Alternatively,the retaining cup may be formed from a metallic material.

The retaining cup may be disposed in the housing and may be formed frommore than one part.

Alternatively, the pivoting means may comprise a plurality of pinsattached to each other in such a way as to form a pivotable arrangement.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be described further, by way of example,with reference to the accompanying drawings, in which:

FIG. 1 is a shift lever mechanism according to the present invention, insection through A-A, showing the lever disposed in a biased neutralposition;

FIG. 2 is the shift lever mechanism of FIG. 1, in section through B-B,showing the lever disposed in a neutral position;

FIG. 3 is the shift lever mechanism of FIGS. 1 and 2, in section throughB-B, showing the lever disposed intermediate the neutral position and apredetermined position, engaging resilient means;

FIG. 4 is the shift lever mechanism of the abovementioned figures, insection through B-B, showing the lever disposed in a predeterminedposition having overcome the resilient means; and,

FIG. 5 is the shift lever mechanism of the abovementioned figures, insection through A-A, showing the lever disposed in a predeterminedposition;

DETAILED DESCRIPTION OF THE INVENTION

Referring to the drawings there is shown a shift lever mechanism 10comprising a housing 12, having a longitudinal axis 14, a lever 16,having a first end 18, a second end 20 and a longitudinal axis 22,pivoting means 24, and biasing means 26.

The housing 12 is cylindrical, formed around the longitudinal axis 14,and comprises a wall 28, having an inner surface 30, and a cover 32.

The lever 16 is formed from an elongate member having an externaldiameter and, in a neutral position, is disposed within the housing 12along the longitudinal axis 14 thereof.

The pivoting means 24 comprises a spherical element 34, having an outerspherical surface 36, and a retaining cup 38, having an inner sphericalsurface 40. The retaining cup 38 is operable to retain the sphericalelement 34 therein and to provide pivotal displacement of the sphericalelement 34, about a pivot point 42, by engagement of the outer sphericalsurface 36 thereof with the inner spherical surface 40 of the retainingcup 38.

The retaining cup 38 may be formed from two or more pieces facilitateassembly of the mechanism.

The spherical element 34 and the retaining cup are formed from aplastics material. Alternatively, they may be formed from a metallicmaterial.

The lever 16 extends through the spherical element 34 and is fixedthereto, intermediate the first and second ends 18 and 20 thereof, byretaining pin 44. The lever 16 is therefore pivotable about the pivotpoint 42.

The biasing means 26 comprises first and second elements, 46 and 48,adapted to be displaceable along the longitudinal axis 22 of the lever16, a third element 50 adapted to be fixed relative to the lever 16, anda biasing element in the form of a spring 52 disposed intermediate thesecond and third elements, 48 and 50, respectively.

The biasing means also comprises stop means 54 in the form of a regionof lesser diameter disposed on the inner surface 30 of the housing wall28 as an abutment 56. The abutment 56 may form part of the retaining cup38 to reduce manufacturing costs.

The first element 46 is in the form of an annular disk having anexternal diameter sufficiently small to be displaceable within thehousing 12 in the direction of the longitudinal axis 14 thereof, andsufficiently large as to abut the abutment 56 disposed on the innersurface 30 of the housing wall 28. The first element 48 also comprises abearing face 47 and an axially opposing abutment face 49. The firstelement 28 also comprises an aperture 58 extending axially therethrough.

The second element 48 is in the form of a bush, of top hat shape, havinga region of lesser external diameter 60 extending to a top end 62 and aregion of greater external diameter 64 defining a rimmed end 66. Therimmed end 66 comprises a rimmed end face 67 and a biasing face 69. Thesecond element 48 also comprises an aperture 68 extending axially therethrough.

The third element 50 is in the form of annular disk having an aperture70 extending axially there through.

In an assembled state, the lever 16 extends through the aperture 58 ofthe first element 46. The diameter of the aperture 58 is greater thanthe external diameter of the lever 16 such that the first element 46 isdisplaceable in the direction of the longitudinal axis 22 of the lever16 whilst disposed other than perpendicular to thereto.

The lever 16 further extends through the aperture 68 of the secondelement 48. The diameter of the aperture 68 is greater than the externaldiameter of the lever 16, such that the second element 48 is slidablealong the longitudinal axis 22 of the lever 16, over the outer surfacethereof.

The rimmed end 66 of the second element 48 is disposed such that therimmed end face 67 abuts the bearing face 47 of the first element 46.

The lever 16 further extends through the aperture 70 of the thirdelement 50. The diameter of the aperture 70 is less than the externaldiameter of the lever 16. A region of the third element 16 around theaperture 70 extends into the external surface of the lever 16 and isthereby fixed thereto.

The biasing element 52 is disposed to surround the region of lesserdiameter 60 of the second element 48 and extend from abutment with thebiasing face 69 of the rimmed end 66 to abutment with the third element50.

The abovementioned pivoting and biasing assembly is retained within thehousing by retaining pins 74 and 76 disposed on the lever 16 in theregion of the first and second ends 18 and 20 respectively thereof. Thelever 16 extends further for user interface beyond the first end 18 andengagement with a transmission system beyond the second end 20.

As shown in the drawings, biasing of the lever 16 may be optimized bysecond biasing means 72 disposed on the lever to oppose the abovementioned first biasing means 26, that is, such that the pivoting means24 is disposed on the lever 16 intermediate the first and second biasingmeans, 26 and 72 respectively, thereby improving the reaction andbalance of the lever 16 in response to the biasing forces.

The second biasing means 72 comprises the same components, and the sameassembly thereof, as the first biasing means 26.

FIGS. 1 and 2 show the lever, in use, in a neutral position, whereineach first element 46 is substantially perpendicular to the longitudinalaxis 22 of the lever 16 and each biasing element 52 is, therefore,extended to support and balance the lever 16 in that neutral position.

FIGS. 3 and 4 show the lever 16, in use, disposed in a predeterminedposition, pivoted along a first plane, defined by section line B-B, andFIG. 5 shows the lever 16, in use, disposed in a predetermined positionpivoted along a second plane, defined by section line A-A, that is,substantially transverse to that of the first plane.

Referring to FIGS. 3 and 4, the first element 46 is axially fixedrelative to the longitudinal axis 14 of the housing 12, to form abearing platform operable to engage with the second element 48.

In use, the third element 50 is axially fixed relative to the lever 16and, on pivotal displacement of the lever, applies a force on a regionof the biasing element 52 adjacent the direction in which the lever ispivoted. The applied force compresses the biasing element between thethird element 50 and the biasing face 69 of the second element 48. Thesecond element 48 is slidable along the lever 16 to allow the lever topivot. However, the greater the pivotal displacement, the greater theforce urging it towards the first element 46, which it is prevented fromtravelling beyond by engagement therewith.

Therefore, the rimmed end face 67, of the second element, bears onto thebearing face 47, of the first element, to produce a returning biasingforce which, through the biasing element 52 and the third element 50, isapplied to the lever 16 and thereby biases the lever into the neutralposition. The returning biasing force is enhanced by the ability of thesecond element to slide along the longitudinal axis of the lever.

Simultaneously, as the third element 50 applies a force which compressesthe biasing element 52 adjacent the direction in which the lever ispivoted, it also applies a cooperative extending force to the biasingelement 52 diametrically opposite the compressing force, which is alsooperable to bias the lever into the neutral position.

Also simultaneously, the second biasing means is operable in the samemanner, as the first biasing means described above, to optimize thereaction and balance the biasing effect on the lever.

Referring to FIGS. 1 and 5, the shift lever mechanism 10 also compriseslever position indication means 78 operable to indicate disposal of thelever 16 in the neutral position.

The lever position indication means 78 comprises a switch 80 operable toengage with switch actuation means 82 to form an electrical signal whenthe lever 16 is disposed in the neutral position.

The switch 80 comprises a connection end 84 and a contact end 86 and isdisposed in the wall 28 of the housing 12 along an axis extendingradially outwards from the spherical element 34. The switch 80 isdisplaceable along the axis in which it is disposed and is biasedtowards the spherical element 34 such that the contact end 86 is incontact therewith. The connection end 84 is connected to a userinterface such as, for example, a visual or audio indicator.

The switch actuation means 82 comprises a member 88 disposed on thecontact end 86 of the switch 80 and a member receiver 90 disposed on thespherical element 34. The member 88 is suitably shaped to ride over thesurface of the spherical element 34 as the lever 16 is displaced intopredetermined positions, as shown in FIG. 5. The member receiver 88 issuitably disposed such that on disposal of the lever 16 in the neutralposition the member receiver 90 aligns with the member 88 and receivesit therein, as shown in FIG. 1, thereby forming an electrical connectionwithin the switch 80. The electrical connection forms an electricalsignal, which actuates the user interface thereby indicating that thelever 16 is in the neutral position.

Referring to FIGS. 2 to 4, the shift lever mechanism 10 also comprisesresilient means 92 operable to provide resistance to displacement of thelever 16 into a restricted position such as, for example, a positionwhich shifts the transmission into a reverse gear.

FIGS. 2 to 4 show progressive displacement of the lever 16 into therestricted position.

The resilient means comprises a resilient member 94 and a detent 96.

The resilient member 94 is disposed in the wall 28 of the housing 12along an axis extending radially outwards from the spherical element 34.The resilient member 94 is displaceable along the axis in which it isdisposed and is biased towards the spherical element 34 such that it isin contact therewith The resilient member 94 has a contact end 98suitably shaped to ride over the surface of the spherical element 34when the lever 16 is disposed in other positions and to engage with thedetent 96 during displacement of the lever 16 into the restrictedposition.

The detent 96 is suitably disposed on the spherical element 34 to engagewith the resilient member 94 only when an attempt is being made todisplace the lever 16 into the restricted position.

In use, on an attempt to displace the lever 16 into the restrictedposition, the resilient member 94 engages the detent 96, which providesresistance to further displacement of the lever 16 in the direction ofthe restricted position. Increasing the force applied to the lever 16 inthe direction of the restricted position, sufficient to overcome thebias applied to the resilient member 94, allows the resilient member 94to ride over the detent 96, thereby allowing the lever 16 to be disposedin the restricted position.

It will be seen from the description that the present arrangementenables a very compact shift lever assembly to be produced. It can havea reduced height above the transmission when compared to known devicesand be smaller because the need for a large spherical pivot element isavoided and the compact biasing means is located on the lever.

Whilst the assembly can work with one biasing means 26, it is preferredto have one above the pivot axis defined by the spherical element 34 andone below it 72. This provides a more balanced feel to the shiftoperation and facilitated easier design and construction of theassembly.

Throughout the description and claims of this specification the words“comprise” and variations of the word, such as, for example “comprising”and “comprises”, mean “including but not limited to”, and are notintended to exclude other components or integers.

1. A shift lever mechanism comprising: a housing including a retainingcup; a lever having a longitudinal axis, said lever being at leastpartially disposed within said housing; a pivoting member in operationalcommunication with said lever being adapted to facilitate pivoting ofsaid lever into a plurality positions; and a lever position indicationmember indicating a disposal of said lever in at least one saidpositions, said lever position indication member being actuated by saidpivoting member, wherein the pivoting member includes a generallyspherical outer surface portion, the retaining cup includes a generallyspherical inner surface portion, the inner surface portion guides alongat least a portion of the outer surface portion as the lever pivotsgenerally about a pivot center relative to the housing, wherein thelever position indication member selectively contacts a portion of thepivoting member that extends radially outward from the pivot center, andwherein the lever position indication member selectively intersects anaxis of rotation of the lever.
 2. The shift lever mechanism of claim 1,wherein said lever position indication member includes a transducermember and an actuation member.
 3. The shift lever mechanism of claim 1,wherein said transducer member includes a switch.
 4. The shift levermechanism of claim 3, wherein said switch includes a potentiometer. 5.The shift lever mechanism of claim 2, wherein said transducer memberincludes an air valve.
 6. The shift lever mechanism of claim 2, whereinsaid actuation member includes a contact member, said contact memberbeing in operational communication with a receiver member of saidpivoting member.
 7. The shift lever mechanism of claim 6, wherein saidcontact member is disposed on said transducer member and said receivermember is disposed on said pivoting member.
 8. The shift lever mechanismof claim 2, wherein said transducer member is disposed on said housing.9. The shift lever mechanism of claim 2, wherein said transducer memberis disposed along an axis extending radially outwards relative to alongitudinal axis of said housing.
 10. The shift lever mechanism ofclaim 9, wherein said transducer member is disposed generallyperpendicular relative to said longitudinal axis of said housing. 11.The shift lever mechanism of claim 2, wherein at least part of saidtransducer member is displaceable relative to at least part of saidpivoting member.
 12. The shift lever mechanism of claim 6, wherein saidcontact member is displaceable relative to said receiver member.
 13. Theshift lever mechanism of claim 6, wherein said contact member isdisplaceable relative to said receiver member along an axis extendingradially outwards relative to said pivoting member.
 14. A shift levermechanism comprising: a housing; a lever having a longitudinal axis,said lever being at least partially disposed within said housing; apivoting member in operational communication with said lever beingadapted to facilitate pivoting of said lever into a plurality positions,wherein the pivoting member includes a generally spherical outer surfaceportion having a detent formed therein, wherein the detent is defined,at least in part, by a detent surface; and a resilient member providingresistance to displacement of said lever in at least one of saidpositions, wherein the resilient member contacts the detent surface asthe resilient member is displaced to provide the resistance.
 15. Theshift lever mechanism of claim 14, wherein said resilient memberincludes a detent.
 16. The shift lever mechanism of claim 15, whereinsaid detent is disposed on said pivoting member.
 17. The shift levermechanism of claim 14, wherein said resilient member is disposed on saidhousing.
 18. The shift lever mechanism of claim 14, wherein saidresilient member is disposed generally along an axis extending radiallyoutwardly from said pivoting member.
 19. The shift lever mechanism ofclaim 15, wherein said resilient member is displaceable relative to saiddetent.
 20. The shift lever mechanism of claim 14, wherein said pivotingmember includes a spherical element.
 21. The shift lever mechanism ofclaim 20, wherein said spherical element is disposed in a retaining cupand is operable to pivotally move therein.
 22. The shift lever mechanismof claim 21, wherein at least one of said spherical element and saidretaining cup is formed from a plastic material.
 23. The shift levermechanism of claim 21, wherein at least one of said spherical elementand said retaining cup is formed from a metallic material.
 24. The shiftlever mechanism of claim 20, wherein said spherical element is fixed tosaid lever thereby forming a pivot point on said lever.
 25. The shiftlever mechanism of claim 20, wherein said spherical element is fixed onsaid lever by a retaining pin.
 26. The shift lever mechanism of claim20, wherein said spherical element forms an integral part of said leverthereby forming a pivot point on said lever.
 27. The shift levermechanism of claim 20, wherein said lever extends through said sphericalelement to form an arrangement generally coaxial therewith.
 28. A shiftlever mechanism comprising: a housing having a housing longitudinalaxis; a lever having a first end and a second end defining a leverlongitudinal axis, said lever being at least partially disposed withinsaid housing; a pivoting member in operational communication with saidlever being adapted to facilitate pivoting of said lever into aplurality predetermined positions; and a lever position indicationmember in selective operational communication with said lever, saidlever position indication member indicating a disposal of said lever inat least one of said predetermined positions, said lever positionindication member being actuated by a portion of said pivoting memberthat extends radially from a pivot center of the pivot member, whereinthe lever position indication member selectively intersects an axis ofrotation of the lever.
 29. The shift lever mechanism of claim 28,wherein said pivoting member is attached to said lever.
 30. The shiftlever mechanism of claim 28, wherein said pivoting member is disposed ina retaining cup.
 31. The shift lever mechanism of claim 30, wherein saidpivoting member is in operational communication with said retaining cup,the pivoting member including a generally spherical outer surfaceportion, the retaining cup including a generally spherical inner surfaceportion, and wherein the inner surface portion guides along at least aportion of the outer surface portion as the lever pivots relative to thehousing.
 32. The shift lever mechanism of claim 30, wherein saidretaining cup is disposed in said housing.
 33. The shift lever mechanismof claim 28, wherein a resilient member provides resistance todisplacement of said lever in at least one of said predeterminedpositions.
 34. The shift lever mechanism of claim 33, wherein said leverposition indication member and said resilient member are disposed onsaid pivoting member.